Category: chemistry

Sun. Nov. 26, 2023 – less than a month ’til Christmas…

Cool and clear, sunny. Yesterday was pretty dang nice. Some clouds, and overcast at the Ren Faire most of the afternoon, but nice temps. It would be great if today was the same.

My summary of my day at the Texas Renaissance Faire is in comments yesterday. I enjoyed it. Not a cheap day out, but a day out in the woods, and there was certainly plenty to look at. D2 enjoyed it, which was the main point.

Today I’m hoping to get some Christmas decor and lighting set up. I’ve got a bunch of new lights and some other stuff for this year, and I don’t have a clear idea of what I have or how to use it best, so I have some experimenting to do. I’m also looking at getting a bunch of cheap artificial trees and setting them up outside as part of the display. A forest of Christmas trees, as it were. We’ll see what I end up with. Figuring it out on the fly is part of the fun for me.

I think that public participation in the rituals and traditions of our culture is vitally important, not only for my own kids, but for the continuation of our culture in general. We celebrate a secular version of Christmas, not a religious one, and yeah, I get the issues with that, but it’s what we do… and Americans basically invented most of that from the whole cloth, or stole bits and pieces shamelessly to suit ourselves. It works for us and provides a framework for the coming month. It builds family memories and traditions too. These ARE the ‘good old days’ so do your best to make sure they are “good”.

We are fighting for our very existence culturally. I’ll take every thing I can that helps.

Stack it up, go the extra mile, be the force for change.


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The Home Scientist Continues!

“RickH” here. I’ve been working with the new owner of The Home Scientist (Ben Siciliano) to rebuild the web site and move it to a new hosting place.

If you have followed along with Barbara’s blog, you might have noticed that Barbara and Ben have come to an agreement for Ben to take over The Home Scientist business. I’ve been working with Ben to get the site rebuilt with new design and some content changes. Most of the changes have been in the ‘back-end’, using PHP functions for commonly-used items to allow those items to be more easily changed.

There will also be a new customer support forum (not quite ready yet) for customers.

The site is available to you, gentle readers (and lurkers), for a ‘beta read’. If you could take a look at the pages to make sure the content looks consistent, and try out the “Buy Now” buttons (make sure you cancel the order on the PayPal checkout page), that would be helpful. You can use the Contact page on the site for any issues or comments.

The new site is currently at . I’d appreciate if you spending a few moments to poke around the site.

Here’s the announcement that will appear on the site (once per day).

I would like to formally announce that The Home Scientist is under new ownership!

Since 2011, the Thompsons have produced a line of high quality, high value science kits in chemistry, biology, and forensic science. To honor their tradition of service, we will continue to offer these kits, which as you’re probably aware, had been created to provide a meaningful laboratory experience for students and enthusiasts – something increasingly difficult to come by these days.

Over the next several weeks, we will be re-stocking the complete line of kits and making it easier for you to obtain technical support for the experiments covered. We’ll also be starting a new customer support forum area.

We’ll be making some changes to the look of this site as we move to our new hosting platform, but our products will still have the same high quality. We thank you in advance for your patience, and welcome your questions, comments, and suggestions for improvement. Please use the Contact Us page for questions or comments.

I’m looking forward to being of service.


Ben Siciliano, the new owner of TheHomeScientist LLC

Ben is restocking all the kits, and hopes to have them all ready by the end of the month.

Thanks for your help on being a ‘beta reader’. And thanks to Ben for agreeing to continue The Home Scientist as Robert and Barbara intend.



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Wednesday, 2 April 2014

07:55 – Barbara is taking the day off work today to make a day trip up to Virginia with her friend Bonnie Richardson. As usual, I tried to convince her to take Colin along. As usual, she deemed that suggestion unworthy of a reply.

I did a phone interview yesterday with Lauren Wolf of Chemical & Engineering News about the S.P.A.R.K. Competition, mostly about the disappearance of real chemistry sets since the 60’s and what S.P.A.R.K. might do to improve the situation. She asked if I knew of any scientists who got their start with a chemistry set, and I told her that she’d be hard-pressed to find any scientist of my generation who hadn’t gotten started in science with a chemistry set. Lauren’s Ph.D. is in physical/bioanalytical chemistry, so I asked her if she’d had a chemistry set as a kid. She hadn’t, but she said she had spent some time in her grandmother’s basement mixing detergents and other chemicals she found there. Of course she hadn’t had a chemistry set. Lauren is young enough to be my daughter, and by the time she should have gotten her first chemistry set, such things no longer existed. More’s the pity.

10:11 – Kit sales still “feel” slow subjectively, but I just checked the figures. In Q1 of this year, our revenues were about 10 times those of 2012Q1 and 1.8 times those of 2013Q1. If that trajectory holds, we’re going to sell a lot of kits this year.

I’ve boosted our batch sizes accordingly. Originally, we made up and bottled chemicals for batches of 15 forensic kits and 30 each biology and chemistry kits. As of now, we’re making up and bottling chemicals for batches of 60 forensic kits and 120 each biology and chemistry kits. The larger runs use our time more efficiently. Which reminds me that I need to get the last half dozen or so solutions made up that we need for another batch of biology kits. And I need to get started on the taxes.

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Wednesday, 26 February 2014

10:34 – As I was making up chemicals yesterday, I thought again about how different chemists pronounce chemical names differently. The first time I remember this happening was my freshman year of college. I used the chemical name strontium and my roommates, also chemistry majors, started making fun of me. I’d pronounced it strawn-chum, whereas they thought it should be pronounced strawn-tee-um. They pointed out that I pronounced calcium cal-see-um. I pointed out that “ti” was not “ci”, that they did not pronounce action ak-tee-on, and that anyway a foolish consistency was the hobgoblin of little minds, adored by little statesmen and philosophers and divines.

A standards body called IUPAC defines official chemistry nomenclature, but the pronunciation of these standard names differs from chemist to chemist. For example, I was making up three liters of dilute acetic acid yesterday. Probably 99% of the chemists I’ve known pronounce that uh-SEE-tik, but I have known more than a few that use different pronunciations, including uh-SETT-ik, ay-SEE-tik, ay-SETT-ik, and probably others. Same deal on many other chemicals, such as phenol. I pronounce that FENN-all, but I’ve heard other pronounce it FENN-ole, FEEN-all, FEEN-ole, feen-OLE, fenn-ALL, and so on.

And when a chemical becomes a functional group name, all bets are off. For example, of the 99% of chemists I know who use uh-SEE-tik, all or nearly all pronounce acetylene as uh-SETT-uh-leen. I don’t believe I’ve ever heard it pronounced uh-SEE-tuh-leen. For that matter, one seldom hears acetate pronounced other than ASS-uh-tate. But I’ve heard acetyl (as in acetylsalicylic acid) pronounced uh-SEE-tul, uh-SETT-tul, and even ASS-uh-TEEL.

The interesting thing is that, as long as there’s no ambiguity, no one seems to care. Everyone just keeps pronouncing chemical names as they wish. No one ever thinks, “Wow. I’ve been mispronouncing that name all these years.”

11:00 – Oh, yeah. I should have mentioned that all bets are off with the Brits, too. One of my favorites is their spelling and pronunciation of aluminum/aluminium. Americans use aluminum and pronounce it al-OOM-ih-num. Brits use aluminium and pronounce it al-you-MINN-ee-um. What’s really odd is that the first spelling and pronuciation was originally British and the second was originally American. They decided they liked ours better about the same time that we decided we liked theirs better.

Of course, with the Brits it’s not limited to chemical pronunciations. Sometimes I think they pronounce words differently just to annoy us. We noticed this frequently while we watching The Borgias recently. Americans pronounce contribute cun-TRIB-byute. Brits apparently pronounce it CON-truh-byute, I think just to be annoying. But my personal favorite is urinal (American YOUR-in-nal), which the Brits apparently pronounce yur-INE-al.

Speaking of annoying, how is that Firefox, currently in something like version 27.0, still uses a British English dictionary rather than a US English dictionary? I mean, US English became Standard English a long time ago. British English is now a dialect.

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Friday, 5 October 2012

08:21 – Barbara took today off work to get some stuff done around the house and yard. This afternoon, she’ll start labeling a thousand or so containers for the new batch of biology kits. I’ll be making up solutions to fill the bottles.

Yesterday, I commented, “Unfortunately, I had no idea if we had any DEET and, if so, where it was. The first thought that crossed my mind, of course, was “I wonder how difficult this stuff is to synthesize.”” A lot of people thought I was kidding, but I was serious. It’s a generational thing.

Our friend Paul Jones is a professor of organic chemistry at Wake Forest University, and is half a generation younger than we are. I suspect that most or all of the time Paul needs a chemical for one of his classes, he just orders it from Sigma or Fisher or Alfa. It didn’t used to be that way. When I started undergraduate chemistry in 1971, the chemistry department ordered a lot of the chemicals they needed, but they also made a lot of them, often liters or kilograms at a time. In fact, it wasn’t unusual for rising junior and senior chemistry majors to have summer jobs at the college. They’d spend the summer doing syntheses. For many of the chemicals, it a lot cheaper to make them rather than buying them, even assuming that they were commercially available. That wasn’t always the case.

I remember talking to one of my chemistry professors, who would have been in his late 50’s at the time. He started off on the “you kids don’t appreciate how easy you have it nowadays” thing. When he was in undergrad chemistry in the 1930’s, he worked summers at the college synthesizing the chemicals they’d need for the following year. He said that about the only thing they bought was common precursors like acids and simple organics. Everything else, they made.

So, yeah, I was serious. My first thought really was, “I wonder how difficult this stuff is to synthesize.”

Speaking of which, I spent some time on the phone yesterday with John Farrell Kuhns, the owner of H.M.S. Beagle, a full-range home science supplies vendor in Kansas City. Among many other goodies, John carries a huge selection of raw chemicals, something like 700+ chemicals at last count. I was telling him that Barbara and I were about to start making up chemicals for a new batch of biology kits, and he commented that sometimes it seemed that he did nothing else all day long except label and fill chemical bottles. Tell me about it.

15:28 – Barbara is labeling bottles while she watches Felicity on Netflix streaming. She started by labeling 15 sets each for the substitute chemicals we ship with the Canadian versions of the chemistry and biology kits, and then got started on 30 sets each of the 15 mL bottles for the US biology kits. She works with a sheet of labels in front of her, a large box of unlabeled bottles on one side of her, and a labeled plastic bag to receive the labeled bottles on the other side of her. She said a few minutes ago that she was running short of the 15 mL bottles, so I went back to the stock room to refill her supply box. When I told her that I’d had to open the next-to-last case of 1,100 of those bottles, she commented that it was time to re-order. Which it will be soon. Those 2,200 bottles are roughly 80 to 100 kits worth, depending on the kit. And as I was refilling her box of unlabeled bottles, it occurred to me that I’d never imagined that I’d ever think that having only 2,200 new 15 mL bottles would constitute a shortage, or that I’d ever be transferring such bottles with a large scoop.

16:03 – So, Barbara is sitting in the den labeling bottles and watching Felicity. For those of you fortunate enough never to have seen this TV series, it’s about a bunch of whiny, obnoxious college students. The women are women, and the men are women too. So, I can hear the audio from my office. The students are sitting in a chemistry lecture, and the professor says, and I quote, “There are three main aspects to stereochemistry: chirality, handedness, and symmetry.” Say what? I shouted in to Barbara that chirality and handedness are synonyms. She thanked me. Thinking perhaps I could help her decipher the plot, such as it is, I then shouted in, “That guy’s not really a chemistry professor; he’s just pretending to be one.” “He’s an actor,” she replied. As though that’s an excuse for reciting garbage lines.

And, speaking of men being men, I saw an article about Zuckerberg the other day that mentioned that he wears the same thing every day, a gray t-shirt, of which he owns about 20 identical ones. He also mentioned that he has one drawer, “like men everywhere.” Ain’t that the truth? I mentioned the article to Barbara, who said she’d already read it and, of course, thought of me.

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Saturday, 21 April 2012

10:37 – Barbara is working on science kits today. I’m doing laundry and working on the forensics book.

I should learn to trust myself. One of the solutions included in the chemistry kit is a sodium salicylate solution that’s 200 ppm with respect to salicylate. It’s used as a standard in a lab session about quantitative determination of salicylate in urine by the Trinder reaction. (Ferric ions react with salicylate ions–actually, almost any phenolic ions–to form an intense violet complex; the intensity of the color is proportional to the concentration of salicylate in the specimens.)

Unfortunately, that dilute salicylate solution is ideal for mold growth, so we have to add a preservative. As I was making up the solution, referring to the instructions I’d printed months ago, I noticed that they mentioned adding a few crystals of thymol as a preservative. That couldn’t be right. Like salicylate, thymol is a substituted phenol, so thymol should also react with ferric ions. So, I thought, dumping an arbitrary “few crystals” of thymol into the solution would ruin its carefully-measured accuracy.

I’d almost decided to substitute a few drops of chloroform as the preservative, but I decided to check just to make sure. So I added one crystal of sodium salicylate to a spot plate, followed by a drop of iron(III) nitrate. As expected, the violet coloration was so intense it looked almost black. I added one crystal of thymol to a second well, followed by a drop of iron(III) nitrate. There was absolutely no visible change.

I really should learn to trust myself. I don’t remember doing it those months ago, but there’s no way I would have added thymol to a salicylate standard solution without checking. What occurred to me now would also have occurred to me then.

Speaking of organic chemistry, I was talking to Paul Jones yesterday and he mentioned that he’d be grading take-home finals for his organic students. Then he mentioned something about the exam focusing on syntheses. I thought what he described sounded a bit much for first-year organic, so I mentioned that to him. It turns out that Paul isn’t teaching first-year organic this year. The final he was talking about was for his grad students. I told him that was a relief, because I was just thinking about asking him if I could take the final, just to see how much (if any) I remembered. Paul was amused. He said I probably wouldn’t do very well on this final, because the synthesis reactions used hadn’t been invented when I was taking first-year organic 40 years ago. (Take that, old guy!) In fairness, Paul did say that the reactions I learned back when dinosaurs roamed the earth typically actually worked pretty well, while the ones his students were learning were sometimes a bit shaky.

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Sunday, 26 February 2012

09:43 – Barbara just gave me a haircut and is vacuuming now. Today we’ll pack the next-to-last group of chemicals for the biology kits: Barfoed’s reagent, Benedict’s reagent (qualitative), bromothymol blue, fertilizer concentrate B, glycerol, neomycin sulfate solution, Seliwanoff’s reagent A, sodium borate, and turmeric reagent.

As I was making up the Benedict’s reagent yesterday, I thought what a great demonstration it’d be for kids. It’s made up as two solutions that are subsequently mixed with constant stirring. The first solution is sodium carbonate and sodium citrate, which is colorless and water-like. I made up 1.7 liters of that. The second solution is copper sulfate in about 200 mL of water. It’s a beautiful blue color, about the same as Crest Pro Health mouthwash. As I poured the second solution into the first, I thought about having kids watch this part. They’d all assume, naturally enough, that the 200 mL of medium blue solution would be diluted by the 1700 mL of water-like solution to yield a much paler blue solution. In fact, the opposite occurs. The more of the copper sulfate solution you add, the deeper the blue color becomes, until the final 1900 mL of solution is a much, much deeper blue than the original copper sulfate solution.

As to why, most people who know a bit about chemistry think copper(II) ions are blue, but in fact they’re colorless. It’s hydrated copper(II) ions that are blue, because they form an intensely blue coordination complex with water molecules. That’s why copper(II) sulfate pentahydrate crystals are blue, while anhydrous copper(II) sulfate is colorless.

Nearly all copper coordination complexes are blue or green of some sort, but the exact color and intensity depends on the ligand. With water as the ligand, one sees the familiar blue of copper(II) sulfate. With citrate as the ligand, the color shifts to a shorter blue wavelength, and the color becomes much, much more intense.

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Friday, 22 July 2011

08:55 – Following the crisis summit, there’s lots of joy in the EU. The feeling among people who don’t understand much about economics is that Greece is saved, the Euro is saved, they’re all saved. Economists and market analysts know better. What the crisis summit accomplished was necessary, but by no means sufficient. All that it really accomplished was to put off the reckoning for a short time, perhaps 90 days or less.

In one very ominous sign, Bulgaria announced that it was putting its plans to join the Eurozone on hold indefinitely. In effect, Bulgaria said that it believes its own currency is stronger than the Euro. And it may well be right. This vote of no-confidence in the Euro will not go unnoticed by investors.

And, of course, Fitch has already declared Greek debt to be in default, with Moody’s and S&P no doubt soon to follow. We’re assured by the Euro authorities that this default is “partial” and “temporary” and “selective”, but as far as investors are concerned, default is default. Nor are investors stupid. They did notice that the crisis meeting left the EU bailout fund at its current level, when it actually needed to be at least tripled in size to have any hope of propping up Spain and Italy as their debt comes due. Investors also noticed that the crisis meeting did nothing to address the critical liquidity problem among European banks. In fact, it worsened it by demanding that the banks “voluntarily” take a hit to their balance sheets on Greek debt, albeit concealing the damage by allowing the banks to continue carrying essentially worthless Greek debt instruments at face value rather than market value.

As hundreds of billions of Spanish and Italian debt matures over the next few months, it’s going to become abundantly clear that the crisis summit accomplished nothing but delaying the problem for a few weeks. Even Keynesian economist Paul Krugman gets it.

Nor is it certain that Merkel and the other leaders of the wealthier northern European countries can deliver what they promised at the summit conference. They have their own legislatures and voters to worry about. German voters almost universally perceive past and future bailouts as simple transfers of money from their own pockets to profligate southern countries, and they’ve had about enough. In Holland, this whole fiasco has accomplished something previously thought impossible: Dutch political parties, from far left to far right and everything in between, are united in their opposition to these huge transfers of their money to southern countries.

So Merkel, Sarkozy, and other leaders are walking a very fine line. Supporting what was needed to actually solve the problem would end up with them and their parties being routed at the polls. That solution, beginning with Eurobonds and ending with full fiscal and political union, is simply unacceptable to voters in Germany, Austria, Holland, and Finland. And rightly so, because the inevitable result would be a united Europe as the world’s newest third-world country.

Anyone who works with plasticware in a lab should keep the chemical resistance of various types of plastics in mind. If it weren’t for the high cost, the various Teflon plastics would be ideal. They’re resistant to almost anything, and anything they’re not resistant to is something I probably don’t want to be using anyway. Polypropylene (PP) and the polyethylenes (LDPE and HDPE) are, with some exceptions, pretty resistant to most chemicals. Polyethylene terephthalate, PET, is most familiar as softdrink bottles. It’s transparent, while PP, LDPE, and HDPE are translucent or opaque, depending on thickness and type. PET is also resistant to most dilute chemicals as well as alcohol and some other organic solvents. What it’s not resistant to, among other things, is concentrated strong acids.

So, yesterday I was down in the lab, making up 2 liters each of various chemical solutions. I was using 2-liter PET Coke bottles as mixing vessels. Among the solutions I was making up was 0.1 M iron(II) sulfate. Like most iron(II) salts, iron(II) sulfate has a nasty habit of spontaneously oxidizing to the iron(III) salt, with the spare iron ions reacting to form insoluble iron hydroxide and iron oxides. The result is a cloudy mess. The way to avoid that is to have sulfate ions present in excess, which is most easily done by adding a small amount of concentrated sulfuric acid to the iron(II) sulfate solution. So there I was, with about 1.5 L of distilled water in a clean 2-liter Coke bottle. I started to add 8 mL of 98% sulfuric acid, and realized as I started to pour what was going to happen.

Yep, as I trickled the concentrated sulfuric acid into the bottle, it ran down the inside of the bottle and instantly started depolymerizing the PET. My pretty transparent bottle turned cloudy white as the PET went from the transparent amorphous form to the opaque semi-crystalline form. I quickly dumped the contents of the bottle down the drain before the PET depolymerized completely. I don’t often have do-overs when I’m making up solutions, but this was one of them.

09:27 – Here’s a pretty amazing video of a group of people in a small boat, at considerable risk to themselves, saving a young humpback whale that had become entangled in a gill net. Even a juvenile humpback could have capsized their boat or turned it into kindling. But the humpback seemed to realize that these humans were trying to help it, and it docilely allowed them to do so. At about 6:30 in, the whale is free. She puts on an incredible display of joy, or perhaps thanks to her saviors. (H/T to Jerry Coyne)

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